An Efficient Diazirine‐Based Four‐Armed Cross‐linker for Photo‐patterning of Polymeric Semiconductors.

A diazirine‐based four‐armed cross‐linker (4CNN) with a tetrahedron geometry is presented for efficient patterning of polymeric semiconductors by photo‐induced carbene insertion. After blending of 4CNN with no more than 3 % (w/w), photo‐patterning of p‐, n‐, and ambipolar semiconducting polymers with side alkyl chains was achieved; regular patterns with size as small as 5 μm were prepared with appropriate photomasks after 365 nm irradiation for just 40 s. The interchain packing order and the thin film morphology were nearly unaltered after the cross‐linking and the semiconducting properties of the patterned thin films were mostly retained. A complementary‐like inverter with a gain value of 112 was constructed easily by two steps of photo‐patterning of the p‐type and n‐type semiconducting polymers. The results show that 4CNN is a new generation of cross‐linker for the photo‐patterning of polymeric semiconductors for all‐solution‐processible flexible electronic devices. [ABSTRACT FROM AUTHOR]